1. Field of the Invention
The present invention relates to a setting device for the control surface or rudder of an airborne body, including a spindle which is actuatable through a control or drive motor, on which spindle there is mounted a follower nut which is secured against rotation and which travels between two end stops, and through the intermediary of which a shaft of the control surface is pivotable by means of a lever about a setting axis.
2. Discussion of the Prior Art
In the specification of U.S. Pat. No. 5,040,745, which is assigned to the common assignee of this application, and the disclosure of which is incorporated herein by reference, there is disclosed a setting device for a control surface or rudder of the type considered herein. In the patent, it is intended to achieve a higher degree of efficiency in the drive train, in that the follower nut is guided within a sleeve which assumes load forces which are transmitted from the shaft of the control surface. This type of construction is expensive in view of the longitudinal or axial bearing required for the follower nut.
Moreover, in the above-mentioned patent, the guidance of the follower nut within the sleeve is expedient inasmuch as the nut engages through the use of a projection between a pair of fingers which are located on the shaft of the control surface. Thusly, the shape of a gear-tooth flank is provided at the juncture while; moreover, the juncture leads to tilting moments being encountered on the follower nut; with such moments having to be assumed by the guidance therefor. Such tilting moments, in principle, exert an adverse effect on the degree of efficiency.